G. De Sanctis

Evidence for an inhibitory role of β-endorphin and other opioids on human total T rosette formation

β-endorphin, met-enkephalin, leu-enkephalin and morphine significantly inhibit rosette formation between human T lymphocytes and sheep red blood cells. This effect is completely reversed by naloxone, a specific antagonist, while naloxone by itself does not influence rosette formation. A further link between the immune system and the neuroendocrine system is suggested.

Psoriasis: comparison of immunological markers in patients with acute and remission phase

The immune system involvement in psoriasis has been documented by the presence of activated T-cells both in peripheral blood and in psoriatic skin lesions and by the intervention of cytokines in the inflammatory process. On this basis, we have undertaken a study in order to examine, in addition to activation markers such as CD25 and CD54 (ICAM-1) on peripheral blood mononuclear cells (PBMNCs) surface, serum levels of soluble interleukin (IL)-2 receptor (sIL-2R), soluble ICAM-1 (sICAM-1), soluble CD4 (sCD4), soluble CD8 (sCD8), beta 2-microglobulin and fibronectin (FN) in psoriatic patients analyzed both in acute and remission phase obtained by topical therapy alone. Our results show that PBMNCs expressing IL-2 receptor (CD25) were increased both in percentage and absolute number in respect to controls, and were not modified after remission. On the contrary, the significantly higher number of CD54+ lymphocytes evaluated in acute psoriasis, showed a reduction during the remission phase, even if the values persisted higher than controls. Serum levels of sIL-2R, sICAM-1, sCD4, sCD8 and beta 2-microglobulin were significantly higher than controls both in acute and remission phase; only FN levels were found to be lower, in patients evaluated both in acute psoriasis and after therapy, in respect to normal donors. On the whole, these results seem to indicate the persistence of both cellular and soluble activation markers even in psoriasis remission phase; in this light, we can suppose that topical therapy alone is not able to efficiently down-regulate activation mechanisms involved in the pathogenesis of the disease.

Overlapping structure of hepatitis B virus (HBV) genome and immune selection pressure are critical forces modulating HBV evolution.

How the overlap between the hepatitis B virus (HBV) reverse transcriptase (RT) and HBV S antigen (HBsAg) genes modulates the extent of HBV genetic variability is still an open question, and was investigated here. The rate of nucleotide conservation (≤1% variability) followed an atypical pattern in the RT gene, due to an overlap between RT and HBsAg (69.9% nucleotide conservation in the overlapping region vs 41.2% in the non-overlapping region; P<0.001), with a consequently lower rate of synonymous substitution within the overlapping region [median(interquartile range)dS=3.1(1.5-7.4) vs 20.1(10.6-30.0); P=3.249×10(-22)]. The most conserved RT regions were located within the YMDD motif and the N-terminal parts of the palm and finger domains, critical for RT functionality. These regions also corresponded to highly conserved HBsAg domains that are critical for HBsAg secretion. Conversely, the genomic region encoding the HBsAg antigenic loop (where immune-escape mutations are localized) showed a sharp decrease in the extent of conservation (40.6%), which was less pronounced in the setting of human immunodeficiency virus (HIV)-driven immune suppression (48.8% in HIV-HBV co-infection vs 21.5% in mono-infected patients; P=0.020). In conclusion, the overlapping reading frame and the immune system appear to have shaped the patterns of RT and HBsAg genetic variability. Highly conserved regions in RT and HBsAg may deserve further attention as novel therapeutic targets.

Characterization of drug-resistance mutations in HBV D-genotype chronically infected patients, naïve to antiviral drugs.

Presence of drug-resistance mutations in drug-naïve hepatitis B virus (HBV) infected patients can seriously compromise response to antiviral treatment. Therefore, our study was aimed at defining the prevalence of HBV drug-resistance in a population of 140 patients, all infected with HBV-D-genotype (the most common HBV-genotype in Eastern Europe, Mediterranean countries and Middle East) and naïve to antiviral therapy. HBV reverse-transcriptase (RT) region was sequenced and analyzed for 20 mutations, confirmed by in vitro studies as associated with resistance to nucleos(t)ide HBV-RT inhibitors (rtL80I/V-rtI169T-rtV173L-rtL180M-rtA181T/V/S-rtT184A/S/G/C-rtA194T-rtS202C/G/I-rtM204V/I-rtN236T-rtM250V). Amino acid changes at other six RT positions, potentially associated with resistance, were also analyzed (rtV84M-rtV191I-rtV207L-rtV214A-rtQ215S-rtI233V). Overall, only 2/140 (1.4%) patients carried primary drug-resistance mutations [rtA181V (0.7%), and rtA194T (0.7%)], while 3/140 (2.1%) patients harbored the secondary mutations rtV173L (1.4%) and rtL180M (0.7%). Additionally, five polymorphic mutations, with a suggested role in drug resistance, were detected [rtQ215S (12.8%), rtI233V (4.3%), rtV214A (3.6%), rtV191I (0.7%), rtV207L (0.7%)]. Notably, no YMDD mutations, namely rtM204V/I, were found. Taken together, the rate of important drug resistance mutations in naïve HBV D-genotype infected patients is today very low, and suggests the potential full efficacy of new-generation antiviral drugs used in first line therapy. Whether such low rate can be extrapolated to non HBV-D subtypes, requires a detailed investigation to be performed in a different cohort of patients.

A randomized controlled trial of amantadine plus interferon-alpha2a vs. interferon-alpha2a alone in naive patients with chronic hepatitis C randomized according to the early virological response to interferon-alpha2a monotherapy.

Background : An early virological response to interferon‐α treatment is a strong predictor of sustained response, but it has never been exploited to stratify patients in clinical trials.

Snapshot on drug-resistance rate and profiles in patients with chronic hepatitis B receiving nucleos(t)ide analogues in clinical practice†

While the selection of complex HBV drug‐resistance patterns on therapeutic failure can compromise the efficacy of anti‐HBV therapies, recent data show that patients failing treatment without drug‐resistance have a rate of virological success close to drug‐naive patients. The goal of this study is defining, in clinical practice, the burden of drug‐resistance mutations in a cohort of patients treated with anti‐HBV drugs. Prevalence and patterns of drug‐resistance were analyzed by RT‐sequencing in 204 patients infected chronically: 148 experiencing virological rebound (defined as an increase in serum HBV‐DNA > 20 IU/ml after achieving virological success [HBV‐DNA < 20 IU/ml]), and 56 null/partial responders (always detectable serum HBV‐DNA [>20 IU/ml] within 48 weeks of therapy). The highest rate of drug‐resistance was observed in patients experiencing virological rebound (prevalence, 79.1%). Conversely, almost half (46.4%) null/partial responders have no evidence of drug‐resistance. The rate of drug‐resistance was higher in patients treated with lamivudine (76.8% [109/142]) and telbivudine (83.3% [5/6]), followed by adefovir (62.5% [15/24]), and entecavir (52.2% [12/23]). Complex mutational patterns characterized by the co‐presence of rtM204V/I‐rtA181T/V (impairing the efficacy of all anti‐HBV drugs) were detected in four patients (2.7%) with virological rebound. Drug‐resistance is the main cause of failure to therapy in patients experiencing virological rebound, supporting the need of rapid switch to anti‐HBV drugs with higher genetic barrier and potency (entecavir/tenofovir). Conversely, nearly half of null/partial responders shows no evidence of drug‐resistance mutations, maintaining high chance of achieving therapeutic success with the same class of drug. In this setting, genotypic resistance may help in selecting patients still carrying wild‐type viruses, that may take major benefits from antiviral treatment. J. Med. Virol. 85: 996–1004, 2013.

Decreased NK Activity in Hairy Cell Leukemia (HCL): An Analysis at the Cellular Level*

SummaryPeripheral blood lymphocytes (PBL) of eleven patients with Hairy Cell Leukemia were studied for surface phenotype and for NK activity against the K 562 cell line (using both the standard 51Cr Release Assay and the Single Cell Cytotoxicity Assay on poly-L-lysine coated coverslips). A significant reduction in NK activity, target binding cells (TBC) and NK active cells (NKa) was detected. In some cases however, despite a very low percentage of NKa, residual NK activity was observed, suggesting an efficient recycling capacity.

PHA-ICC, ADCC and NK in patients with ANLL in CR: Human fibroblastic interferon fails to increase NK-active cell frequency

PHA-ICC, ADCC and NK activity of PBL were studied in ten patients with ANLL in CR and in eighteen normal controls in the presence and absence of HFIF. No statistically significant differences were recorded among the two groups with regard to basic lymphocyte functions. Although the parameters of lymphocyte function remained analogous for those tested, the analysis at the single cell level revealed that HFIF stimulation increases the number of NK active cells and target binding cells among normals, but not in leukemic patients.

Childhood Abnormal Expansion of Large Granular Lymphocytes

An expansion of large granular lymphocytes (LGL) in the peripheral blood (PB) of a 10-year-old child is described. After a long history of uncertain hematological diagnosis and chemotherapeutic regimens and 2 years after any kind of therapy, the child showed in PB an expansion of LGL E-rosette+, OKT3+, OKT8+, Leu7+. Cytotoxic activities showed high natural killer activity and an increase of PHA-induced cytotoxicity. Histological findings in the spleen, abdominal lymph nodes and bone marrow excluded a lymphoproliferative disease, but liver biopsy revealed a chronic aggressive hepatitis.

Ultrastructure of lymphocyte-mediated cytotoxicity. II. Interaction between human lymphocytes and antibody-coated chicken erythrocytes

In the course of antibody-mediated lymphocyte cytotoxicity, ultrastructural studies show interaction between effector and target cells characterized by interdigitations. The significance of the observation is discussed.